| 摘要 |
PROBLEM TO BE SOLVED: To produce an optical disk having a recording film segmented between tracks to increase spacing loss and capable of eliminating a magnetic effect. SOLUTION: A groove part 22 is concentrically or spirally disposed on the top side of a disk substrate 20, a pair of side walls having different angles θ1 and θ2 to the plane direction of the disk are formed on both sides of the bottom 22B of the groove part 22 and a recording film is formed on the top side of the disk substrate to produce an optical disk. In this method, a steeply slanting side wall 22A as one of the side walls is set in the range of 80-90 deg. to the plane direction of the disk, a gently slanting side wall 22C as the other is set in the range of 24-66 deg. to the plane direction of the disk and the formation of the magnetic film is avoided on at least the steeply slanting side wall. The recording film is segmented between tracks to increase spacing loss and a magnetic effect can be eliminated. |
